New bridges over troubled waters

The opening of the Bailey bridge, next to the Hikuwai No.1 bridge north of Tolaga Bay in June of last year. Two new bridges, 2.5 metres higher than the previous ones, are to be installed where State Highway 35 crosses the Hikuwai River north of Tolaga Bay.Picture by Liam Clayton

Work begins this month on permanent replacements for two bridges crossing the Hikuwai River on State Highway 35, north of Tolaga Bay.

Hikuwai No. 1 bridge was destroyed in Cyclone Gabrielle last year, initially cutting access north and south of the river.

While Hikuwai No. 2 bridge was not damaged in the cyclone, it will also be replaced in order to match the same height of the new No.1 bridge  to protect it from future weather events.

Transport Rebuild East Coast (TREC) crews will be designing and building the bridges through recovery funding.

TREC project director Tony Gallagher said it was an opportunity to design and build more resilient bridges.

“Our team of designers and engineers have looked at a number of options and have made key changes to the new bridges to improve the resilience.”

Both new bridges will be 2.5 metres higher, supported by rounded piers set further apart and built on concrete piles.

“Raising the bridges gives more clearance to allow for waterflow while the rounded piers will be set further apart to minimise the chance of wood debris getting stuck underneath.”

NZ Transport Agency Waka Kotahi national manager of infrastructure delivery Mark Kinvig said the current Bailey bridge — installed near the destroyed Hikuwai No.1 bridge — and nearby Pourau Road bypass had limitations for heavy transport operators and the longevity of the connection for communities.

“Bailey bridges are only a temporary solution and are vulnerable. A new weather event could cause damage to the bridge and risk the road closing.

“We know these new bridges will make a difference to local communities, businesses and people travelling the road to have a secure, future-proofed connection.”

Mr Gallagher said consenting for the project fell under the Severe Weather Emergency Recovery (NZ Transport Agency Waka Kotahi) Order 2023.

“This allows the project to be delivered faster by granting consents in a shorter time frame as long as all the consenting requirements are met.

“We’ve been working with local iwi, Gisborne District Council and landowners to get the project to this point, and TREC will be holding two community drop-in sessions for locals on Wednesday, March 13.”

The sessions are in Tokomaru Bay between 4pm and 5.30pm at The Haven Senior Citizens’ Association; and at Tolaga Bay between 6.30pm and 8pm at Hauiti Hauora.

“At these sessions, people will get the chance to learn more about the project and speak to the project team delivering it.

“We’re excited to get this project under way. Until now, we’ve been heavily focused on recovery work to restore access to parts of the state highway network. While we’re continuing to prioritise that, we’re also focusing on permanent solutions such as this one at Hikuwai,” Mr Gallagher said.

The resource consent for the project has been lodged and TREC is expecting to be able to begin the project later in March.

Between March and June, a second Bailey bridge and a temporary road will be installed to allow traffic to continue moving while the new No.1 and No.2 bridges are being built at the locations of the original bridges.

The road between the two new bridges will also be built up to meet the new bridge height.

TREC crews expect the two new bridges will be opened by the end of this year.